Radiator core



1.. R. CHASE 1,993,872

RADIATOR CORE Filed April 6, 1932 March 12, 1935.

6127a: 73. Chile Patented Mar. 12, 1935 UNITED STATES PATENT OFFICE- msasrz RADIATOR 001m ware Application April 6, 1932, Serial No. 603,492

8 Claims. (01. 257-) This invention relates to heat exchange devices, and particularly to a core for radiators of the type in general use as a part of an automobile engine cooling system.

It is an object of the invention to provide an improved radiator core construction of relatively simple but rugged design, which will be easier and less expensive to manufacture, with reference to both the forming and assembling operations and the amount of material required.

A further object of the invention is to provide a core of the cellular type in which the walls of the water passages and the fin plates are provided with portions which mutually cooperate in centering the parts during assembly, and in maintaining them in proper relation and against displacement in use, together with other mutually cooperating portions, which assist in the transfer of heat and increase radiation efliciency by producing tortuous fluid flow paths to thoroughly break up and impart turbulence to the flowing streams without materially restricting flow; such portions being constituted by formations integral with the core strips, whereby the amount of material required is not appreciably increased and the complete formation of the respective strips in a single operation is possible.

A better understanding of the invention will be had upon reference to the accompanying drawing wherein Figure 1 is an elevational view showing a core and tank assembly; Figure 2 is a perspective view with parts in section of a portion of the core, and Figure 3 is a vertical sectional view of the core.

Referring to the core and tank assembly shown in Figure l, the numeral 1 indicates the upper header or inlet tank and 2 the lower header or outlet tank, the intermediate heat transfer unit or core being indicated at 3. When used as an automobile radiator this assembly is usually incased in an ornamental shell, and the two tanks are connected with the cooling jacket of the engine block. Hot water or other cooling medium passes from the engine jacket to the upper tank 1 and then flows downwardly through the water passages of the core 3 into the lower tank 2 for return to the engine. In the passage of the coolant through the core the heat taken up by it in the engine block is dissipated or transferred to a stream of air passing over the water tubes.

As to the core structure, this includes a series of spaced water passages which extend between and connect the inlet and outlet tanks, each passage consisting of a hollow space between or interiorly of apair of walls or preformed strips AA,

whose opposite edges are joined together and sealed, and a series of separator or spacer strips B--B within the spaces between the adjacent pairs of strips A-A to properly locate the parts and afford a number of closely related heat radiating 5 fins which divide the intervening spacing into a number of small cells for the flow of air through the core.

In the manufacture of the core the strips A and B are formed to shape by rolls or presses from thin ribbons of copper, brass or other suitable metal. As the ribbons come from the form ing machines, they are cut to given lengths, the strips A usually being a little more than twice the length of the strips B. The wall strip A is 15 then. folded back upon itself and joined at its two ends, and with aseparator strip B interposed between the two walls of the folded strip, constitutes a sub-assembly unit which is then grouped side by side with other similar units so that the adjoining walls of succeeding units provide a water passageway between them. Instead of forming sub-assembly units in the manner referred to, and which is the preferred and most convenient method of assembly, the several strips can be cut all to the same length and then stacked in the proper relation. After the strips are brought together, their opposite edges are joined and sealed, the usual practice being to clamp the strips in a suitable fixture and dip the front and 30 rear faces of the core first in a flux and then in a solder bath. The solder not only seals the water passages, but it also unites the walls and spacers and holds the parts as a unitary assembly.

In the present instance, the formation of each wall strip A is such that it is generally of zigzag or corrugated shape, although only the relatively narrow portions 5, adjacent each edge, are regular in corrugations throughout the length of the strip. The angular ridges of the corrugations on 40 opposite faces of the strip are indicated by the numerals 6 and 7, respectively, with each ridge 6 exteriorly of the water passage being unbroken or extending continuously from one edge to the other of the strip. In line with each ridge 7 on 45 the interior face of the strip, the material intermediate the portions 5-5 is reverselybent or pressed outwardly, as at 8, to afford spacing between the adjoining walls, and in this outwardly pressed intermediate portion there are formed a 50 series of rounded depressions or pimples 9 spaced apart at intervals and projected outwardly beyond the apices of the ridges 6 and into the air cell passageway. As shown in the drawing, the corrugated end portions 5 are nested together with the ridges 6 of one strip in seating engagement with the ridges 7 of the other plate, so that the depressions 9 on the two walls are arranged in staggered relation. It will be obvious that the depressions 9 not only increase the normal size of the water passageway, but also afford interior deflecting surfaces, and in effect, a transverse succession of tortuous paths open one to the other, whereby a thorough agitation and turbulence of the flowing liquid results to assist materially in the transfer of heat. Furthermore, the irregular outer surfaces afforded by the depressions aids in mixing the particles of air passing thereover and through the air cell.

With reference to the separator plate B, this is shown in the drawing as consisting of a corrugated and imperforate strip with the corrugations extending back and forth between the adjacent walls A-A of adjacent pairs of water tubes, to form a series of heat radiating fins 10. At the bight or reverse bend between succeeding fins, there is formed a reentrant groove or angular seat 11 that receives and centers a corresponding ridge 6 on the wall strip.

To afford a large radiating surface area, the corrugations in the plate B are made deeper than those in the strip A, although the pitch is the same so that each ridge in succession has, in effect, a pair of divergent heat radiating fins projecting from it. It may be pointed out here that the contact between the seating surfaces of the ridge 6 and the groove 11 is continuous from edge to edge, which insures good transference of heat into the fin. The heat transference is further facilitated by the soldered bond that can be had, because of the close contact of the unbroken contacting surfaces. That is to say, there results in the soldering operation an inward flow by capillary attraction of both fiuxing fluid and molten solder between the surfacesof the ridge 6 and reentrant portion 11.

In each fin 10 there is preferably formed a transverse succession of projections 12 pressed alternately in opposite directions out of the plane of the fin. These embossments are also alternately inclined from one side to the other, with reference to the plane of the fin, the higher portions being toward the wider portion of the air cell space defined by the fin. By this arrangement, each air cell in a direction transversely of the core, has a sinuous formation, as can be seen readily in Figure 2 of the drawing, and this irregular path, which is furthered by the row of rounded embossments 9 in the wall of the water tube projecting into the cell, so stirs the air column as to continuously sweep the air particles into and out of contact with the walls of the cell, whereby a more uniform absorption of heat takes place throughout the whole mass of the air column.

In addition to serving the purposes heretofore mentioned, the embossments 9 have a part in the proper assembly of the core strips. These bosses lying on both sides of each ridge 6 and projecting beyond the apices of the ridges, afford inclined guiding and centering surfaces on which the fins may ride to bring the reentrant portions 11 into engagement with the mating ridges 6 for the proper and automatic centering of these parts.

On the interior face of each wall strip A and intermediate the corrugated margins 5, there is shown in the drawing a series of angular projections 13 in longitudinal alinement. The inclined side of the projections on one wall fit or engage with those on the other wall of each water passage, so that the two sets of projections nest together in the same fashion as do the mating marginal portions 5. There is thus afforded an intermediate spacer arrangement which is particularly advantageous when the transverse width of the core strips is relatively large, in that the walls are definitely and positively spaced apart and held against inward collapse. It is of course desirable to make the walls as thin as possible to get best heat transference and to keep down costs, and without the projections 13 in a wide core the construction is too flimsy to insure a soldered bond for the entire depth of the core between the seating portions 6 and 11. However, with the addition of these spacing projections 13 the core is strengthened and a good solder bond is obtained. Furthermore, it has been found that the flow of water through the tube is materially increased since the walls are held against collapse or inward deflection. In cores of greater width a larger number of rows of intermediate spacers can be used. For example, it has been found that in cores of approximately two and one quarter inches in width, a single row of projections as shown in the drawing will be sufiicient, and that for cores of three and four inches in depth the best results are had when two and three sets of projections in transverse spaced relation are employed.

From the above description, it will be apparent that there is provided a light weight core of simple but sturdy design, which insures a thorough agitation of flowing air and liquid streams, whereby maximum capacity and a high factor of efiiciency is obtained.

While a preferred embodiment only is here specifically disclosed, it will be obvious that the invention is capable of such modification as comes within the scope of appended claims.

I claim:

1. In a radiator core, a plurality of wall strips spaced apart to provide fluid passages therebetween and arranged in pairs with the strips of each pair joined together along their edges to form a closed tube therebetween, a series of transverse ridges on each wall arranged in spaced relation to each other and projected away from the tube and toward the fluid passage between succeeding tubes, with the ridges on each wall longitudinally offset to the ridges on the next adjacent walls, a series of rounded embossments between succeeding ridges in transversely spaced relation, and projecting out of the plane of the wall away from the tube and toward the fluid passage between succeeding tubes so as to increase the size of the tube and provide bailies in the passage, the embossments in one wall being longitudinally offset to those in the other wall of each tube and cooperating to provide a transverse succession of tortuous paths separated one from the other by parallel sided paths, and an imperforate corrugated fin strip in each fluid passage between the tubes spacing said tubes and extending from one to the other in zigzag fashion, transversely extending reentrant seats at the reverse bends between succeeding fins to receive and center said ridges, and a series of projections pressed out of the plane of each fin from opposite sides thereof in transverse alternate succession and inclined to the plane of the fin with the inclinations of the projections on opposite sides of the fins extending in opposite directions, said projections providing baflies and imparting a sinuous form to the fin for cooperation with said embossments in producing turbulence of the fluid.

2. In a radiator core, the combination of a pair of spaced apart wall strips each having a series of spaced ridges extending thereacross, and an undulating fin strip between the walls having at each reverse bend a reentrant groove adapted to receive one of said ridges, and in each fin a transverse corrugation with the corrugations of the several fins cooperating one with another to afford a sinuous air passage.

3. In a radiator core, the combination of a pair of wall strips spaced apart to provide an air passageway therebetween, each strip having a series of V-shaped ridges spaced apart, and a series of outwardly extending projections arranged in alternate relation with said ridges and extended beyond the tops of said ridges, and a separator strip within the air passage extending back and forth between the wall strips in zigzag fashion to provide a series of fins, said strip having reentrant V-shaped grooves between successive fins and on each side thereof to seat said ridges, and the fins being adapted to ride on said projections to bring the ridges and grooves into engagement.

4. In a radiator cor the combination of a pair of wall strips spaced apart to provide an air passageway, and a separator strip of zigzag formation providing fins for spacing the wall strips, mating seating portions on the respective strips and raised bosses on the respective wall strips and between the seating portions, said bosses extending beyond the seating portions of the wall strip into the air passageway and providing inclined guiding and centering surfaces for the seating portions of the separator strip.

5. In a radiator core, the combination of a corrugated fin strip having reentrant grooves at the apices of the corrugations and on each side of the strips and a pair of wall strips, each having a series of ridges for mating with said grooves and a series of projections alternating with and extending beyond said ridges and providing inclined guiding and centering surfaces for the sliding engagement of the fin strip to bring the grooves and ridges into seating relation.

6. In a radiator core, the combination of corrugated fin strip having reentrant grooves at the apices of the corrugations and on each side thereof, and a pair of wall strips, each having a series of ridges adapted for seating engagement with said grooves, and portions of the wall between said ridges projected beyond the ridges into the space between the walls.

7. In a radiator core, the combination of a pair of spaced wall strips each having a series of bosses projecting out of the plane thereof toward but in offset relation with the bosses on the other strip, and a corrugated fin strip spacing said wall strips and providing a succession of spaced fins connected successively by reverse bends, mating seats located respectively at the reverse bends between successive fins and between bosses onthe wall strips, said bosses extending into the space between the wall strips and beyond the seats thereon and being adapted to act as guiding surfaces for engagement by the fins to bring the seats together. I

8. In a radiator core, the combination of a pair of spaced tubes, the adjacent walls of which are provided with longitudinally spaced transverse ridges, with the ridges on one wall arranged in staggered relation to those on the other wall, and spacer means between said walls including a succession of imperforate fins extending between the staggered ridges in alternately inclined rela tion, with adjacent pairs of fins defining a single stack of substantially triangular air cells arranged in successively reverse order with the bases of adjacent cells provided by portions on opposite walls between said ridges, reentrant portions at opposite ends of each fin connecting adjacent ends of next succeeding fins at the apex of each air cell to seat said ridges, each base portion having therein a series of spaced pimples extending into the adjacent air cell and beyond said ridges to provide fin-guiding and centering surfaces on both sides of said ridge and each fin having transversely stepped formations.

LINUS R. CHASE. 

